Hook coupling



Aug, 24, 1943. G, R. UN'rHANK ETAL HOOK COUPLING Filed Nov. 6, 1942 2 Sheets-Sheet l Fig- A.ug.' 24,- 1943.

G R. UNTHANK ETAL HOOK coUPLING Filed Nov. 6, 1942 2 Sheets-Sheet 2 Fig'. 5.`

Fig. 4-

lkw/ENT@ @s George. RodMamUvHfhmnK Honra A'hu'r J'ohn 5\ He Patented Aug. 24, 1943 HOOK COUPLING George Rodham Unthank, New Southgate, London, and Henry Arthur John Silley, London,

England Application November 6, 1942,` Serial No. 464,752 In Great Britain November 20, 1941 e claims. f'(01. 294mg) 'I his invention relates to hook couplings of the kind including a pair of hooks arranged to overlap each other when in the closed position to form a part of a ring Iadapted to engage an eye of a;

exert on the hooks a turning moment in the opening direction which is large enough to over- CII use on the rope of a crane, derrick, hoist.' winch or the like whereby disengagement from the load may be effected at the required moment with certainty.` A further object is to provide such a coupling which is capable of instantaneous release from the load whilst still subjected to scribed by way of example with reference to the accompanying drawings, in which:

Figs. 1 and 2 are side elevations of 'a form of the coupling suitable for relatively light loads, shown closedand opened respectively,

Fig. 3 is an end elevation of the same coupling when closed,

Figs. 4 and 5 are side elevations of a heavy duty coupling shown closed and opened respectively, and

Fig. 6 is an end elevation of this heavy-duty coupling when closed.

In the example shown in Figs. 1, 2 and 3, the coupling body comprises front and back wall plates IIJ and I I of elongated form held in suitable spaced relationship by spacing bolts I2 (omitted from Fig. 3) and a block I3 to which the plates I and II are secured by screw studs I4 and which is provided with a swivelling shackle I5. Near the end of the body opposite to the shackle end a pair of hooks I6 and I1 of generally arcuate form are mounted to rock intermediate their ends about pivots formed by pins I8 and I9 extending through the front and rear plates II) and II. These pins are parallel with one another and symmetrically disposed in spaced relationship on the two sides respectively of the centre line of the coupling body. l

The working ends of the hooks are shaped to overlap one another when in the closed position to form a part of a ring for engagement with the eye 22 or equivalent member of the load, but the eye-engaging surfaces and 2I are so formed that, when viewed in a direction parallel tothe axes of the pivot pins I8 and I9, they are .approximatelyV perpendicular to the longitudmal centre line of the coupling so that the load will come the frictional resistance of the eye 22 on the hooks and of the pivot pins so that the hooks tend to open under load.

The other ends of the hooks are also arranged to overlap but .in the open position, and these ends are pivotally connected by pins 23 and 24 to links 25 and Z which are coupled to one end of a tension member formed by a rod 21 mounted for guidedV longitudinal movements of limited extent within the coupling body. The links are connected to the rod 21 through a common pin zextending through an eye-lug 30 at the end of the rod 21 and through slots 29 of limited length formed in the body wall plates I0 and II whereby limitation of the movement of the rod is achieved. The upper end of the rod is guided in a bore 3| in the block I3.

The rod 21 is held in one of its extreme positions by the engagementc-f a detent 32 in a recess 33 formed in the rod 21. The detent is xed to a shaft Sli rotatable in bearings in the plates I0 and II, and a lever 35 is xed to the shaft 34 to enable the detent to be rocked at the will of an operator to release the rod 21 for movement.

When the rod 21 is retained by the detent 32, the links hold the hooks closed upon the eye or equivalent member of the load, as shown in Figs. 1 and 3, and in thisposition the` pivotal connections of the hooks I6 and I1 and the links 25 and 2S are substantially co-axial. When the detent 32 is moved to the position shown in Fig. 2 and the rod 21 is thus freed, the hooks open under the pull of the load, and they are caused to make similar and simultaneous movements by the links 25 and 26 as the rod 21 moves towards the hooks, the ends of the links connected with the hooks taking up symmetrically disposed positions on each side of the centre line of the coupling body.

Preferably the wall plates Il andV Il of the coupling body extend to approximately the working ends of the hooks and are slotted to provide pairs of spaced guiding horns 36 which engage on each side of the eye or equivalent member of the load when said eye is held by the hooks, and serve to guide said eye and prevent it from following either one ofthe hooks as the latter move to the open position.

A lifting eye 31 is provided outside the coupling body at at least one end of the common pin 23 connecting the links and the movable rod 21,

- in order to enable the rod 2l and the links to be moved and the hooks closed. The detent 32 and the operating lever 35 therefor are so shaped and disposed that the detent makes automatic retaining engagement with the recess 33 in the rod 21 by gravity, When the rod 21 has been moved to the required extent.

The heavy-duty coupling shown in Figs. 4, 5 and 6 Vis generally isimilar' to the example just described, and corresponding'parts are denoted by the same reference numerals with the addition of A in the second example.

There are, however, important differences in the details of the arrangement of the hooks and the means for locking them" irr the closed 'position. ,of

The pivot pins 18A and IQA of the hooks are again parallel to one another andi symmetrically disposed in spaced relationship on` -thetwosi'des respectively of Athe centre line of the.coupling body, the seatings of these pins on the body Wall -plates-"being Vreinforced bylfrings suchy as -zise- I`"cured t'o ltheseplates fby Welding.' Each hook Vbea-rson itsy pivot pinover thel-Whole :lengthqoi A'fthat part of the pin lying 'between thegringsfw.

The Working ends of thehun-ks'arefsteppedyas -fshown'inFgsgi and f5, so as tooverlap one another when inthe closed positionz .i` fs 1 IITheouter 4"end oi'fthea'hookl-E'IA is of reduced thickness at 39 and carries a pinnZA serving as a y connection fori a pair=of rlinks 1Min lyingaonef-cn l l`each'side of therfhook. v'Theyotherfend.-cf.=the hook I SA'is forkecliat this fork being pivotally -connectedfbyl a pin iBAltofcne-endgof alink-QZEA *sthe 'otherencly ofcwliich is"connectedyitogether Yr-Pwithfhe links 28A, :byakpin-SA, to a forked flug lSA.- at the end of4 a compression v member, .EIA lamounted for guided longitudinalmovement withfin the coupling body; y The compression.. member 21A. is held in the position shown irl-Fig. adetenttEA co-operating Witha .step v133Aformed e on the compression member.- Y IThe lever arms otthe-.hooks lil-EA, HA, between the pivot pins IAflAfand 'the link .pi'nsfA ---24Ag co-operate respectively with t'l'ielinksZA, -f l2-BA to -form two .-'like are soarranged that the r mechanical advantage, in the sense from the hooks to the sli,dabl'e,com j pression rrieniizier275A,- is relatively low .when the coupling is-closed, the .tc'ggles then being intheir Afully- -fbre-ken position', as-.shcvn in' fig-and that yfthe `mechapical l advantagelincreases Vas` the'pcou- -pling opens,the toggles then vapproaclliing "their straightA position. 1.by this arrangementtheA axial y load imposed on thev compressio'rilmember-by the ,--l flinksis minimised, 'and'tl'i` Vlease; `(ifdetent is accrdingiy' facilitate-C1.

if We'claim'i. v Y

l. Ahook coupling of the kind specified including a coupling lo'ody bearing .a shackle atoheend, v .apair o-r" hooks'pivoted on the' bo'dy neairit y'other end andy arranged t`ol`ov'ei'laponeanotherimthe closed position to form' a part oia ring-foren- -ffgagement with an eye of a load, the Workingends Yofsaicl hooks beingsov shapedthat 'tbieyjtend to incveintc"y tlieopen position under-the pal load; a member mountedioi'" nitedfmov fvvithin said coupling bodyjtwolinks respectively .connecting Asaid vhooks with said movrlenie'mr ber for maintaining -said"hoC'iks closed-whensaid movable lrfieinb'er is'in Apositioii4 suclJtha-t the loadirnposes through sa'dfllinks 'a'vforacapable or displacing said movable-member in onel'sense, a'movatie (rerentror retaining said movable-.mem- "ber against such displacement, fana: controll means uml. L 1 l. '1 A jm" I ,K

togglefmechanisin's which for releasing said detentand therebyipe'rniitting said displacement of the movable member as the load opens said hooks.

2. A hook coupling of the kind speciiied in- 5 cluding a coupling body bearing a shackle at one end, a pair of pivot pins on said body near its other end disposed transversely and on opposite sides respectively of the longitudinal centre line Vvofsaid body; aipair of-hookslpi/voted on said pins respectively and having working ends capable of overlapping one another in the closed position yto form a part of a ring for engagement with an Yeye-of a load, said working ends being so shaped that they tend to move into the open position -underfthapullgofthe load, a member mounted Y -forlimited-'movement within said coupling body,

two links respectively connecting said hooks with ',--s-aidfmovable member for maintaining said hooks rsfc'losed'whenrsaid movable member is in a position such that the load imposes through said links a Aiorcecapable of displacing said movable member sin:onefsnsetaissuable;detentanrataiaiearsaid .-fmovable-membarsaeainst Such displassmentaaild .control'-means "fora releasing;,saidd Y ent d 25. thereby :permitting saidiisplace entJv qfthegn'olv- 'fable,, rrreI-nbery as-the-.load ppensfsa A xhooi Y w 3. A hook coupling olivi. Weakinmspecied cluding a couplingsboly bearingfa shackle l.at one 6nd,-,l a pair; 0l pivot; pms ,ong said body! ne* its :otherilend disposed vtransi/ersely, anida-.on lapposite s sides respectively ofgthe long itudinallcenme ,line `fof-fsaid body,a pair ofllhookspvoted 'onfsaid pins vrespectively and/.having.,-Working- ,ends capab ',.lof

..overlappingen@anotherJin,th closed.positionneV Y of a,.load said working lends being so shapedmthat s v`taining,saidlioeks ,closed `when saidtensionrneinv aber; islfin; aposton such. bataille load' imposes through Saidaliliksa OrQeraQabIQQf displacing .said tension memberint onesense.; a 'ieter'itqnovably mounted on said coupling bodyfor'retain- -ingf said tension..vlrieinber against,fsucli displace-V -^ment. Yarlcltmltrorl rmeansbperable ilfvfmlrleasing said detent and thereby permitting saiddis acegmentbf. the; tension, member,as they loa' opens said hooks, and means for movingsaidtension .memberintosaidone position,.M'WHl A if'. ...nlaA`. hool:A couplingjofwthe kind specified inis engaged Maid Sl/Qfsiglsaid ,warliiriaensls'lhlne j bers; for. limited .longitudinalmovement? tW0 links respectively; connected... io. said ,.liqoks 'at iarts thereof? which overlap one 'another in' v`the iipen position, saldi links being :also connected -tosaid form .a .partici a ring. for. engagement. with ancre said wall members and capable of holding said tension member in a position such as to retain said hooks in their closed position, and control means operable for disengaging said detentl from said tension member, each of said links at al1 times lying at an angle of between 90 and 180 degrees with a line joining the center of the pivot of the respective hook to the center'of the connection of the link with the hook..

5. A hook coupling of the kind specied including a coupling body bearing ashackle at one end, a pair of hooks pivoted on the body near its other end and arranged to overlap one another in the closed position to form a part of a ring for engagement with an eye of a load, the Work- -ing ends of said hooks being so shaped that Jthey tend to move into the open position under the pull of the load, a member mounted for limited movement within said coupling body,'two links respectively connecting said hooks with said movable member for maintaining said hooks closed when said movable member is in a position such that the load imposes through said links a force capable of displacing said movable member in` a pair of pivot pins on said body ne'ar its other end disposed transversely and on opposite sides respectively of the longitudinal centre line of said body, a pair of hooks pivoted on said pins re spectively and having working ends capable of overlapping one another in the closed position to form a part of a ring for engagement with an eye of a load, said working ends being so shaped that they tend to move into the open position Under the pull of the load, and said hookshaving lever ends which extend on the side of the respective pivot pins remote from said Working ends and which are shaped to'rock towards and away from eachother without overlapping each other, a compression member mounted for limited longitudinal movement within said coupling body, two

position, and control means operable for releasing said detent to permit the load to open said hooks. i GEORGE RODHAM UNTHANK. HENRY ARTHUR JOHN SILLEY. 

